[PATCH 04/12] pci: epf-test: Use driver registers as volatile

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

The pci-epf-test driver uses struct pci_epf_test_reg directly from the
test register bar memory to execute tests cases sent by the RC side.
Make sure to declare pci_epf_test_reg use as volatile to ensure that
modifications to the fields of that structure make it to memory to be
seen by the RC side on completion.

Also initialize the test register bar to 0 when it is allocated.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
---
 drivers/pci/endpoint/functions/pci-epf-test.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 030769893efb..df3074667bbc 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -340,7 +340,7 @@ static int pci_epf_test_copy(struct pci_epf_test *epf_test)
 	struct device *dev = &epf->dev;
 	struct pci_epc *epc = epf->epc;
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
-	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+	volatile struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
 
 	src_addr = pci_epc_mem_alloc_addr(epc, &src_phys_addr, reg->size);
 	if (!src_addr) {
@@ -441,7 +441,7 @@ static int pci_epf_test_read(struct pci_epf_test *epf_test)
 	struct pci_epc *epc = epf->epc;
 	struct device *dma_dev = epf->epc->dev.parent;
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
-	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+	volatile struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
 
 	src_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
 	if (!src_addr) {
@@ -530,7 +530,7 @@ static int pci_epf_test_write(struct pci_epf_test *epf_test)
 	struct pci_epc *epc = epf->epc;
 	struct device *dma_dev = epf->epc->dev.parent;
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
-	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+	volatile struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
 
 	dst_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
 	if (!dst_addr) {
@@ -619,7 +619,7 @@ static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test, u8 irq_type,
 	struct device *dev = &epf->dev;
 	struct pci_epc *epc = epf->epc;
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
-	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+	volatile struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
 
 	reg->status |= STATUS_IRQ_RAISED;
 
@@ -653,7 +653,7 @@ static void pci_epf_test_cmd_handler(struct work_struct *work)
 	struct device *dev = &epf->dev;
 	struct pci_epc *epc = epf->epc;
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
-	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+	volatile struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
 
 	command = reg->command;
 	if (!command)
@@ -911,6 +911,7 @@ static int pci_epf_test_alloc_space(struct pci_epf *epf)
 		dev_err(dev, "Failed to allocated register space\n");
 		return -ENOMEM;
 	}
+	memset(base, 0, test_reg_size);
 	epf_test->reg[test_reg_bar] = base;
 
 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
-- 
2.39.1